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我需要在解析云代码中编写beforeDelete函数，有多个查询以下代码将删除所有评论，但不会删除图像

注意：帖子对象有 2 列（关系和关系）图像和评论是自定义类

例如

Parse.Cloud.beforeDelete("Post", function(request, response) {

    // delete all its comments
    const commentsQuery = new Parse.Query("Comment");
    commentsQuery.equalTo("postId", request.object.get("objectId"));
    commentsQuery.find({ useMasterKey: true })
        .then(function(comments) {
            return Parse.Object.destroyAll(comments,{useMasterKey: true});
        })
        .catch(function(error) {
            response.error("Error finding comments line 91 " + error.code + ": " + error.message);
        });

        // delete all its images
        const postQuery = new Parse.Query("Post");
        postQuery.equalTo("postId",  request.object.get("objectId"));
    //  postQuery.include("images");

        postQuery.first({useMasterKey: true})
            .then(function(aPost){
                var images = aPost.relation("images");
                images.query().find({useMasterKey: true}).then(function(foundImages){
                        return Parse.Object.destroyAll(foundImages,{useMasterKey: true});
                    }).catch(function(error){
                        response.error("Error finding images line 107 " + error.code + ": " + error.message);

                    });
            })
            .catch(function(error) {
                console.error("Error finding related comments " + error.code + ": " + error.message);
                response.error("Error finding post line 113 " + error.code + ": " + error.message);
            });

            response.success();
});

编辑

解析日志

    2018-03-19T00:33:50.491Z - beforeDelete failed for Post for user undefined:
  Input: {"User":{"__type":"Pointer","className":"_User","objectId":"LZXSK7AwE7"},"Content":"","Title":"ios ui, coffee shop app","isPublic":true,"createdAt":"2017-11-23T06:37:55.564Z","updatedAt":"2018-03-19T00:32:30.180Z","views":2,"images":{"__type":"Relation","className":"Image"},"mainColors":{"__type":"Relation","className":"Color"},"Comments":{"__type":"Relation","className":"Comment"},"objectId":"3UDJCIXxGS"}
  Error: {"code":141,"message":"Error finding images line 107 undefined: A promise was resolved even though it had already been resolved."}

如何解决此问题以成功销毁其所有图像和评论

4

1 回答 1

1

我建议将代码重新组织成更小的可测试的、承诺返回的函数，就像这样......

function commentsForPost(postId) {
    const commentsQuery = new Parse.Query("Comment");
    commentsQuery.equalTo("postId", postId);
    return commentsQuery.find({ useMasterKey: true })
}

function destroy(objects) {
    return Parse.Object.destroyAll(objects,{useMasterKey: true});
}

function imagesForPost(post) {
    let images = post.relation("images");
    return images.query().find({useMasterKey: true});
}

现在 beforeDelete 函数清晰而简单......

Parse.Cloud.beforeDelete("Post", function(request, response) {
    // get the post's comments
    let post = request.object;
    return commentsForPost(post.id)
    .then(comments => destroy(comments))
    .then(() => imagesFromPost(post))
    .then(images => destroy(images))
    .then(() => response.success());
});
于 2018-03-20T04:09:17.630 回答